In the past, many establishments, such as scientific laboratories, micro-electronic manufacturers, testing labs, hospitals, and the like, have required relatively clean air from which substantially all dust particles, micro-organisms, and pathogens have been removed. Normally atmospheric air contains many thousands of particles per cubic foot and due to air filtering systems certain classifications of air have been established. For example, Class 10,000 indicates that there are 10,000 or less particles of a size 0.5 micron and larger in one cubic foot of air and Class 100 indicates that there are 100 or less particles of a size 0.5 micron and larger in one cubic foot of air. Even though filters have been developed which can remove substantially all of the particles and micro-organisms from the air, it has been difficult to maintain the air in a clean room at a desired level due to the people who are in the room, as well as the necessity for providing ingress and egress to the room. In some cases, such as in the manufacture of micro-electronic parts, a yield rate of 30% has been acceptable. In order to improve the maintaining of clean air in a clean room, special permanent structures have been designed and built using laminar airflow and recirculation paths for the air and the people who are located in the clean room have worn non particle generating lab coats and in some instances have worn non particle generating gloves, boots, hats and masks.